Some implementations described herein provide a laser device. The laser device includes a first portion of the laser device, at a proximal end of the laser device, that includes one or more optical devices, where the first portion is configured to emit first electromagnetic waves having a first wavelength. The laser device includes a second portion of the laser device, at a distal end of the laser device, that includes an optical crystal configured to receive the first electromagnetic waves and to emit second electromagnetic waves having a second wavelength based on reception of the first electromagnetic waves, where the optical crystal includes a thin film coating disposed on an end of the optical crystal, the thin film coating configured to: support emission of the second electromagnetic waves from the optical crystal, and support internal reflection of the first electromagnetic waves within the optical crystal.